Quick Math Function Question

Sully

Hey,
I'm trying to figure out exactly how you approach this function (attached two examples). Its the vot + so I have never came across before. I have other examples which are more normal examples.

Thanks.

V0 = Velocity at 0 (time 0)
V0t doesn't really make sense. Surely it's Vt that makes the equation correct?

With V0 being the velocity at t=0 = given the question?

EDIT: I see that it is using an approximation of acceleration instead of actual acceleration.

What the function is doing is giving you an approximation of change in height due to gravity (-4.875t^2) and then also the change in height due to the initial velocity.

Its an odd way of calculating it imo.

So it's saying that Height of Ball at Time t = -4.875 t ^2 + Initial Velocity * t + Initial Height.

LeixlipRed

This equation relates displacement or distance to velocity. Here the height of the ball is given after a certain amount of time has elapsed. It is also a quadratic function in t so the ball will move in a parabolic motion. v_0 is the initial velocity, i.e. the velocity at time t=0. To derive this you can calculate the derivative with respect to t, which is the velocity at a given t, sub in t=0 and you'll see that it's equal to v_0.

s_0 is the initial height of the ball. Sub t=0 into the equation to derive this, i.e. what is the height at time t=0? This is the y-intercept also if you plot height on the y-axis and time on the x-axis.

So now you must decide from the info given in the question what v_0 and s_0 are and that should be easy if you follow my explanation.

Eliot Rosewater

In those questions you initially treat v0 and s0 as constants, and use differentiation to find them given the initial values in the question.

sponsoredwalk

This looks like some kind of leaving cert question :mad: I hate these kinds of
things! I really really really advise you to learn how to derive all of this
from some calculus and the meaning of acceleration (caused by force/gravity!).

https://www.youtube.com/watch?v=KOKnWaLiL8w

This & maybe the start of the second lecture will give you all you need to
know about this idea, or at least the motivation & logic behind what's
going on!

LeixlipRed

Eliot Rosewater wrote: »

In those questions you initially treat v0 and s0 as constants, and use differentiation to find them given the initial values in the question.

I thought we weren't here to do people's work for them?

Sully

LeixlipRed wrote: »

I thought we weren't here to do people's work for them?

Jesus. Its not a project, an assignment or anything else related to cheat my way through something. I'm well past that, but thanks for the indirect compliment.

Its something I came across in old material, which isn't in more recent material I have so I said id ask here. If thats a problem, ill ask Math questions elsewhere.

While I know you guys may not like giving answers to students for their assignments (cant say I have ever known such assignments to be given in college that allow for time to ask on Boards) I find giving the workout to a solution can be very helpful and useful for students. But, its not relevant in my case, just a pointer based on several years of experience dealing with Maths and various people who have moons of Math education and are professors in such.


Thanks.

LeixlipRed

I wasn't giving out to you, it was aimed at the poster who done the work for you. Who are we to know it's not an assignment, etc,. Of course we're here to give you the help but consider this example, which is better, to teach you to add all numbers or to tell you 2+2=4? The posts preceding that post gave you all the information you needed to do the question. The ethos here is that we provide the theory and background necessary for the problem a person is having but we don't actually do the sum out for them

Secondly, it's the internet, we've no idea who is submitting stuff here for help. Hence why we have a general rule in the charter covering assignments, etc,.

Anyway, feel free to post any maths related problems you have!